1. Field of the Invention
The present invention relates to a nucleic acid, a protein encoded by the nucleic acid, a recombinant organism having the nucleic acid introduced therein and a protein produced by the recombinant organism.
2. Related Background Art
A spider silk is known as a naturally occurring high performance polymer with excellent toughness due to a combination of strength and elasticity. A spider has at most 7 specialized glands, from which many types of spider silk different in nature are produced, and among them, attention has been focused on a dragline produced by Major Ampullate as the toughest spider silk in the development of new materials used in various industrial fields such as medical, aviation and apparel industries.
A protein called Major Ampullate Spidroin (MaSp) is known as a major protein constituting a dragline, and up to now, gene sequences encoding MaSp proteins of various spiders such as Latrodectus hesperus, Latrodectus geometricus and Nephila clavipes have been elucidated (Non-Patent Literature 1: Nadia A. Ayoub et al., Blueprint for a High-Performance Biomaterial: Full-Length Spider Dragline Silk Genes, 2007, Issue 6, e514; Non-Patent Literature 2: William A. Gaines IV et al., Identification and Characterization of Multiple Spidroin 1 Genes Encoding Major Ampullate Silk Proteins in Nephila clavipes, Insect Mol Biol, 2008, 17(5), 465-474; and so on.).